<template>
	<div class="type-nav">
		<div class="container">
			<div @mouseleave="leaveIndex" @mouseenter="enterShow">
				<h2 class="all">全部商品分类</h2>
				<!-- 三级联动 -->
				<transition name="sort">
					<div class="sort" v-show="show">
						<div class="all-sort-list2" @click="goSearch">
							<div class="item" v-for="(c1,index) in categoryList" :key="c1.categoryId"
								:class="{cur:currentIndex == index}">
								<h3 @mouseenter="changeIndex(index)">
									<a :data-categoryName="c1.categoryName"
										:data-category1Id="c1.categoryId">{{c1.categoryName}}</a>
								</h3>
								<!-- 二三级分类 -->
								<div class="item-list clearfix" :style="{display:currentIndex == index?'block':'none'}">
									<div class="subitem" v-for="(c2,index) in c1.categoryChild" :key="c2.categoryId">
										<dl class="fore">
											<dt>
												<a :data-categoryName="c2.categoryName"
													:data-category2Id="c2.categoryId">{{c2.categoryName}}</a>
											</dt>
											<dd>
												<em v-for="(c3,index) in c2.categoryChild" :key="c3.categoryId">
													<a :data-categoryName="c3.categoryName"
														:data-category3Id="c3.categoryId">{{c3.categoryName}}</a>
												</em>
											</dd>
										</dl>
									</div>
								</div>
							</div>
						</div>
					</div>

				</transition>
			</div>
			<nav class="nav">
				<a href="###">服装城</a>
				<a href="###">美妆馆</a>
				<a href="###">尚品汇超市</a>
				<a href="###">全球购</a>
				<a href="###">闪购</a>
				<a href="###">团购</a>
				<a href="###">有趣</a>
				<a href="###">秒杀</a>
			</nav>
		</div>
	</div>
</template>

<script>
	import {
		mapState
	} from 'vuex';
	// 引入节流
	import throttle from 'lodash/throttle';
	export default {
		name: 'TypeNav',
		data() {
			return {
				// 存储鼠标移上哪一个一级分类
				currentIndex: -1,
				show: true,
			}
		},
		// 组件挂载完毕：可以向服务器发送请求
		mounted() {
			
			if (this.$route.path != '/home') {
				this.show = false;
			}
		},
		computed: {
			...mapState({
				categoryList: (state) => {
					return state.home.categoryList;
				}
			})
		},
		methods: {
			// 鼠标进入修改响应式数据currentIndex属性
			changeIndex: throttle(function(index) {
				// 鼠标移上某一个一级分类的元素的索引值
				this.currentIndex = index;
			}, 50),
			// 一级分类鼠标移出的事件回调
			leaveIndex() {
				if (this.$route.path != '/home') {
					this.show = false;
				}
				this.currentIndex = -1;
			},
			// 进行路由跳转的方法
			goSearch(event) {
				let element = event.target;

				let {
					categoryname,
					category1id,
					category2id,
					category3id
				} = element.dataset;

				if (categoryname) {

					let location = {
						name: 'search'
					};
					let query = {
						categoryName: categoryname
					}

					if (category1id) {
						query.category1Id = category1id;
					} else if (category2id) {
						query.category2Id = category2id;
					} else {
						query.category3Id = category3id;
					}
					// 判断:如果路由跳转的时候,带有params参数,捎带传递过去
					if(this.$route.params){
						location.params = this.$route.params;
						location.query = query;
						this.$router.push(location);
					}
				}
			},
			// 当鼠标移入的时候,让商品分类列表进行展示
			enterShow() {
				if (this.$route.path != '/home') {
					this.show = true;
				}
			}
		}
	};
</script>
<style scoped lang="less">
    .type-nav {
        border-bottom: 2px solid #e1251b;

        .container {
            width: 1200px;
            margin: 0 auto;
            display: flex;
            position: relative;

            .all {
                width: 210px;
                height: 45px;
                background-color: #e1251b;
                line-height: 45px;
                text-align: center;
                color: #fff;
                font-size: 14px;
                font-weight: bold;
            }

            .nav {
                a {
                    height: 45px;
                    margin: 0 22px;
                    line-height: 45px;
                    font-size: 16px;
                    color: #333;
                }
            }

            .sort {
                position: absolute;
                left: 0;
                top: 45px;
                width: 210px;
                height: 461px;
                position: absolute;
                background: #fafafa;
                z-index: 999;

                .all-sort-list2 {
                    .item {
                        h3 {
                            line-height: 30px;
                            font-size: 14px;
                            font-weight: 400;
                            overflow: hidden;
                            padding: 0 20px;
                            margin: 0;

                            a {
                                color: #333;
                            }
                        }

                        .item-list {
                            display: none;
                            position: absolute;
                            width: 734px;
                            min-height: 460px;
                            background: #f7f7f7;
                            left: 210px;
                            border: 1px solid #ddd;
                            top: 0;
                            z-index: 9999 !important;

                            .subitem {
                                float: left;
                                width: 650px;
                                padding: 0 4px 0 8px;

                                dl {
                                    border-top: 1px solid #eee;
                                    padding: 6px 0;
                                    overflow: hidden;
                                    zoom: 1;

                                    &.fore {
                                        border-top: 0;
                                    }

                                    dt {
                                        float: left;
                                        width: 54px;
                                        line-height: 22px;
                                        text-align: right;
                                        padding: 3px 6px 0 0;
                                        font-weight: 700;
                                    }

                                    dd {
                                        float: left;
                                        width: 415px;
                                        padding: 3px 0 0;
                                        overflow: hidden;

                                        em {
                                            float: left;
                                            height: 14px;
                                            line-height: 14px;
                                            padding: 0 8px;
                                            margin-top: 5px;
                                            border-left: 1px solid #ccc;
                                        }
                                    }
                                }
                            }
                        }

                        &:hover {
                            .item-list {
                                display: block;
                            }
                        }
                    }
                    .item:hover{
                        background: skyblue;
                    }
                }
            }
            
            .sort-enter{
                height: 0;
            }
           .sort-enter-to{
                height: 461px;
            }
            .sort-enter-active{
                transition: all .5s linear;
            }

            
        }
    }

</style>